When opening a 1.13.2 world ,which had shulker boxes placed down, in the latest snapshot causes the shulker boxes to lose whatever was inside them.
When opening a 1.13.2 world ,which had shulker boxes placed down, in the latest snapshot causes the shulker boxes to lose whatever was inside them.
Isn't because you upgraded your world, it's because you 'reloaded' the world with upgrading. Duplicate of MC-138938.